Project Summary Men continue to be missed by HIV testing and treatment services. Index partner testing is a critical strategy for reaching men. Index HIV self-testing (HIVST), whereby ART clients take HIVST kits home to their sexual partners for testing, is a new strategy that dramatically increases index testing among men, and is being taken to scale across Malawi. However, only 25% of men identified as HIV-positive through Index HIVST initiate ART after 6- months. Innovative strategies to increase ART initiation and retention among men are urgently needed. The overarching goal of the proposed K01 is to develop and pilot a home-based ART intervention (ART initiation + 3-months ART care) to increase ART initiation (primary outcome) and 6-month viral suppression (secondary outcome) among men who test HIV-positive through Index HIVST in Malawi. Candidate: I am a social scientist with a background in HIV research in sub-Saharan Africa. My long-term goal is to transition from observational social science to clinical trials research in innovative HIV service delivery models among hard-to-reach populations, such as men. I am applying for a five-year K01 award to obtain training, mentorship, and research experience. Mentoring: I have an exceptional multi-disciplinary mentoring team with extensive experience in HIV care and management and clinical trials in the region. The team has complementary expertise in social science and clinical trials in HIV service delivery models (Dr. Thomas Coates ? Primary Mentor), best practices in HIV care and management and differentiated models of care in Malawi (Drs. Judith Currier and Risa Hoffman), scalability and sustainability of interventions (Dr. Sundeep Gupta ? Malawi-based), and advanced biostatistics (Dr. Ron Brookmyer). Career Development: To achieve my long-term goals, we have developed a detail plan to build skills in four additional areas: (1) best clinical practices for ART care and maintenance; (2) clinical trials in novel approaches to HIV service delivery; (3) advanced statistical methods; and (4) ethics in clinical trials research in low-resource settings. Research Activities: The specific aims accompanying the career development plan are to: (1) Develop a home-based ART intervention for male partners tested through Index HIVST, using in-depth interviews with male Index HIVST users (n=15-20) and their partners (n=15-20), and focus group discussions with key informants (n=18-30). (2) Determine the potential effectiveness of home-based ART versus standard facility-based ART (on ART initiation (primary outcome) and 6-month viral suppression (secondary outcome) among male Index HIVST users in a pilot trial with 200 HIV-positive men. Expected Outcomes: Results from this study will inform definitive trial to test home-based ART services for men identified as HIV-positive through index HIVST strategies. The project will also give me the additional skillsets needed to become an independent investigator in clinical trials.